Agricultural combine harvesters are typically designed to cut off crops at ground-level, separate non-grain plant matter from the crop portions of the plant, save the crop portions to a holding tank or reservoir, and discard the non-grain plant matter at the rear of the vehicle.
Often, the non-grain plant matter, includes, without limitation, stems, cobs, stalks, leaves, and branches. The term crop residue may be used to describe this generally non-grain plant material. This term is indicative of the historical relative value of grain and non-grain material. The crop residue is chopped at the rear of the combine harvester and distributed over the ground where it is broken down by microbes in the soil and provides fertilizer for the next growing season's crops.
In recent years, however, there has been a growing movement to recover this non-grain plant matter and to use it for secondary processes, such as for a biomass material for ethanol production. Thus, this non-grain plant matter has value beyond its traditional usage. The collection of the material can either occur simultaneously with grain harvest in a single pass operation, or collected after grain harvest, in a multiple pass operation. In a single pass operation, the non-grain plant material can be collected after it is chopped at the rear of the vehicle and is directed into a “stover” cart or similar wheeled container that is towed behind the combine harvester to receive the non-grain plant matter, while the grain is collected in the combine grain tank. In a multi-pass operation, the non-grain material can be left on the field during grain harvest and collected during subsequent field operations, using a baler, forage harvester or similar machinery
What is needed, therefore, is an apparatus for varying the amount of chopped non-grain plant material that is distributed over the ground while the vehicle is underway. What is also needed is a way of automatically varying the amount of chopped non-grain plant material that is deposited on the ground based upon soil parameters, crop parameters, terrain parameters or other environmental or regulatory factors.
It is an object of this invention to provide such an apparatus.